本研究探討公司治理機制，尤其董事會與審計委員會，對企業非一般公認會計原則（Non-GAAP）盈餘可比性之影響，並以 2005 年至 2024 年美國公司為對象。實證結果顯示，較高的董事會獨立董事占比及審計委員會開會頻率，能顯著提升Non-GAAP 盈餘可比性。
額外分析進一步發現，董事會與審計委員會監督效能的發揮層面存在本質差異，獨立董事對財務品質的控制效果較為全面，其在 GAAP 環境中亦能穩定發揮，且在面臨外部經濟政策或公司層級之營運不確定性波動時，其對 Non-GAAP 品質的約束能力皆會受到激發；相對地，審計委員會監督效果則因資訊屬性與風險來源而異，在資訊屬性方面，不同於 Non-GAAP 品質依賴頻繁日常會議，受嚴格規範的 GAAP 財報則更仰賴主席之精力投入；在風險來源方面，審委會的控制成效僅能在外部經濟政策不確定性高時穩定發揮，一旦面臨公司層級之營運不確定性，其監督效能則會受到抵銷。

This study examines the impact of corporate governance mechanisms, specifically the board of directors and audit committee, on the comparability of Non-GAAP earnings, focusing on U.S. companies from 2005 to 2024. The empirical results indicate that a higher proportion of independent directors on the board and a greater frequency of audit committee meetings can enhance a firm's Non-GAAP earnings comparability.
Additional analyses further reveal inherent differences in the dimensions where the monitoring effectiveness of the board and the audit committee manifests. Independent directors exhibit a more comprehensive control effect on financial quality, which stably functions within the GAAP environment and is significantly activated when facing either external economic policy uncertainty or firm-level operational uncertainty. In contrast, the monitoring effects of the audit committee vary depending on information attributes and risk sources. Regarding information attributes, unlike Non-GAAP quality which relies on frequent routine meetings, strictly regulated GAAP reporting depends more on the chair’s dedication of time and energy. Regarding risk sources, the controlling efficacy of audit committee meetings stabilizes only under high external economic policy uncertainty, whereas its monitoring effectiveness is completely offset when confronting firm-level operational uncertainty.

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